theqdor steinway



(No Model.)

0. F. T. STEINWAY. Piano Sounding Board Bridge.v

No. 233,710. Patented Oct. 26, I880.

Iggy/re 1.

N.FETE.RS PHOTO-UTHOGRAF'HER WASHINGTON. D C.

UNITED STATES PATENT ()FFICE.

G. F. THEODOR STEINW'AY, OF NEW YORK, N. Y.

PIANO SOUNDlNG-BOARD BRIDGE.

SPECIFICATION forming part of Letters Patent No. 233,710, dated October 26, 1880.

Application filed May 13, 1880.

To all whom it may concern Be it known that I, O. F. THEoDoR STEIN- WAY, of the city and State of New York, have invented certain Improvements in Composite Sounding-Board Bridges, of which the following is a specification.

It has heretofore been customary to construct sounding-board bridges of a single homogeneous material.

As it is the function of the bridge to transmit vibrations to all those parts of the sounding-board with which thebridge is in contact, it is desirable that there should be the utmost facility for the propagation of vibrations in the bridge itself, in order that vibrations generated in a string, for example, near one end of the bridge may be energetically propagated through the entire length of the bridge, and hence be communicated not only to those parts of the sounding-board in the immediate vicinity of the vibrating strings, but to the more distant parts of the soulnling-board.

My present invention is based upon my observation of the fact that vibrations are more readily set up in, and are more energetically propagated by, a bridge consisting of several alternate layers of hard and soft wood; and my invention consists of a sounding-board bridge composed of several comparatively wide thin strips of hard wood, preferably maple, glued to and united by correspondingly wide sheets of soft wood, preferably pine, these alternate layers of wood being set edgewise upon the sounding-board, and being usually surmounted by and glued to a capping strip of hard wood, in which the stringpins are inserted.

The accompanying drawings, representing a sounding-board bridge embodying my invention, are as follows:

Figure 1 is a top view of a portion of the scale of a piano-forte, showing part of the sounding-board, the bridge, and a few of the strings. Fig.2is a transverse section through the line a: a: on Fig. 1, exhibiting the manner in which the sounding-board bridge is built up of different strips, and the manner in which it is applied to the surface of the soundingboard.

It will, of course, be understood that my in- (X0 model.)

vention may be used in both horizontal and upright pianos, that the sounding-board A may be of any desired shape, and that the bridge B may be suitably curved to adjust it to the requirements of the particular scale in which it may be employed.

The principal portion or foundation of my improved bridge is composed of the thin strips of hard wood 0, which set edgewise upon the surface of the sounding-board, and are separated from each other by the sheets of soft wood D, which are respectively interposed between and glued to the strips of hard wood.

The upper edges of the several adjoining layers of wood are glued to the inner face of the capping-strip E, which is made of hard wood in order that it may afford the proper hold for the string-pins F, between which the strings G are strained.

The lower edges of the adjoining layers of wood constitute the bottom of the bridge, which is secured in the usual manner to the surface of the sounding-board.

It will be found that with a bridge constructed substantially in this 1nannerthat is, by the union of strips of hard wood with interposed sheets of soft wood-the vibrations of each string will be propagated over alarger area of the sounding-board, and the volume of tone will be thereby largely increased.

The capping-strip E, although not absolutely indispensable, yet gives a finish to the appearance of the bridge, and also adds to the stability of the structure and afiords a secure seat for the string-pins.

I claim as my invention, for use in a pianoforte 1. Acomposite sounding-board bridge built up of adjoining layers of hard and soft wood, substantially as and for the purpose set forth.

2. The combination, in a piano-forte, of the sounding board A with the bridge 13, constructed of the strips 0, of hard wood, glued to the interposed sheets D, of soft wood, and provided with the capping-strip E, substantially as described.

(J. F. THEODOR STEINWAY. Witnesses:

M. L. ADAMS, EDWD. PAYSON. 

